Pump



Sept. 2l, 1948.

Filed March '7, 1946 r Sept, 21, 1948. H. s. BANcRoFT 2,449,832

PUMP

Filed March 7, 1946 2 Sheets-Sheet 2 Patented Sept. 2l, 1948 PUMP s Howard l S. Bancroft, Sharon, Pa. Application Maren 7, 194e, serial No. 652,634 i F lThis invention relates to pumps, and, more particularly,` to pumps including pistons having a combined rotary and reciprocating action With a port type valving action. f

'1It is the general object of my invention to provide an improved pump or -compressor and characterized by Simplicity of design, inexpensiveness of structure, high efciency, and long life with a minimum of maintenance.

Another object of my invention is the provision of a pump having a piston which is given `a combined rotary and reciprocating motion by rugged and positive, but simple, mechanism.

Another object of my invention is to provide an improved valvirigv action in a pump and characterized by a rotary cup which covers and uncovers the valve ports.

Another object of my invention is the provision of 4a pump design which is particularly adapted to be built with one or more cylinders Vand in any desired capacity. `I `Another object is to provide a pump having very high volumetric efliciency resulting from a minimum head clearance and unusual valve structure.

The foregoing objects of my invention, and other objects which will become apparent as the description proceeds, are achieved by a pump including a cylinder, a piston,`means for simultaneouslyrotating and reciprocating the piston in thecylinder, a valve cup rotatably mounted in the head end of the cylinder and slidably receiving"` the head end of the piston, a spline connection between the cup and piston whereby the cup is rotated without reciprocation by the piston, inlet and exhaust ports in the head of the cylinder, and a port in the cup adapted to register with the inlet and exhaust ports in timed relation with the reciprocation of the piston.

For a better understanding of the invention, reference should be had to the accompanying drawings, wherein Fig. 1 is a vertical sectional view parallel to the axis of the crankshaft and taken through one embodiment of a pump incorporating the principles of the invention; Fig. 2 is a vertical cross-sectional view taken on line II--II of Fig. 1; Fig. 3 is a plan view of the head end of the cylinder with the head removed, as taken on line III- III of Fig. 1; Fig. 4 is a bottom plan view of the cylinder head; Fig. 5 is a side elevation of a modified manner of driving the piston; and Fig. 6 is a view similar to Fig. 5 but taken at right angles thereto.

In the drawings, the numeral I0 indicates a cylinder slidably and rotatably receiving a piston 6 Claims. (Cl. 10S- 157) I2 in the form of a solid cylindrical body. `.The piston is reciprocated by a crank I4 which `slidably and rotatably carries a block I5 on its crank armbearing, the lblock' |'6' rotatably receiving-a pin I8 which is fastened rigidly in the piston I 2.` A4 nut 20 and locking' cotter key hold the blockv IE on the pin I8.

The pin is simultaneously rotatedasit is reciprocated, and this `is achieved by the provision of4 a circular camway 22 in the piston which camway .slidably engages with a. roller cam 24 rotatably supportedin fixed relation on a threaded plug 26 carried by the cylinder I0. From Figs.` 1 and 2,- it will be recognized the shape ofthe camway 22 is such that reciprocation of the piston `will also cause rotationthereof. The piston I2 is free to rotate inasmuch as the pin IB turns freely in the block I 6; andduring the rotation ofA the piston the block I6 slides back and forth on the unusually long Vconnecting rodbearing of the crankshaft `I4.` l 4 As shown in Figs. 5 and 6, an alternate manner of driving the piston I2 is to form it with a slot 50 which slidably receives a cross head 52 secured to a shaft 54.' The shaft 54 is held in suitable.

bearings (not shown) and is adapted to be ro` tated by `a motor. The rotation of the shaft 54 rotates the piston which is reciprocated by they roller cam 24 engaging in the camway 22.

bolts 30, is a head 32"Which is provided with arcuate port-s 34 and36, for intake and exhaust respectively. `Positioned between the head 32 and the cylinder I D is a cup40, `which is carried in a"r`ec`ess`42 in the cylinder so that the cup may rotate but is held against movement axiallyof the cylinder. The inside of the cup forms'a con*- tinuation of the cylinder bore and slidably receives the piston.

The piston l2 serves to rotate the cup 40., and this is achieved by providing a key and spline connection 44 between the two whereby the cup is rotated as the piston turns although the piston is reciprocating and not the cup.

The closed end of the cup is formed with a valve port 46 which alternately registers with the intake and exhaust port-s 34 and 36 as the cup is rotated and the piston is reciprocated, all as will be understood, to provide the positive dis placement pumping action as the crank shaft I4 is rotated. Of course, any suitable prime mover is -connected to the crank shaft I4 to effect rotation thereof. l

Lubrication of the working parts of the apparatus may be provided for by forced feed, splash,

known character, and if the intake and exhaust' ports are reversed the pump can be operated as a compressed air, steam or like motor.

While in accordance with the provisions' of the patent statutes, I have specically illustrated and described one best known form of my invention,

3. Apparatus of the type described including a cylinder, a piston slidably received in the cylinder, a crank shaft having an extra wide connecting rod bearing, a block slidably and rotatably carried on the bearing, a pin rigidly secured to the piston and rotatably secured to the block, cam and cam way means between the piston and cylinder for rotating the piston when the piston is reciprocated by the crank shaft, a head on the cylinder having intake and exhaust ports therein, a cup supported between the head and cylinder for rotary but non-axial movement, the inside of jthe cup forming a continuation of the bore of it should be particularly understood I am not to be limited thereto or thereby but that the scope of my invention is dened in the appended claims;

I claim:

11. Apparatus of the type described including a cylinder, a .piston slidably received in the cylinder, a crankshaft having an extra wide connecting-rod bearing, a 'block slidably and rotatably carried on the bearing, a pin rigidly secured to the piston and rotatably securedto the block, cam and cam way means between the piston and cylinder for rotating the piston when the piston is reciproca-ted by the-.crank shaft, a head on the cylinderv having intaker and exhaust ports therein, a cup supportedfbetween the head and cylinder for rotary but non-axial movement, the inside of the-cup forming a continuation of the bore oi the cylinder and slidably receiving the head end of the piston, a spline and key connection between the piston and cup whereby rotation of the piston effects rotation of the cup', said cup having a port in its end and alternately registering lwith the intake and exhaust ports in timed relation with the reciprocation ofthe piston.

2.. Apparatus of the type described including a cylinder, a piston slidably received .in the cylinder, means for simultaneously rotating and reciprocating the piston in the cylinder, a head on the cylinder having intake and exhaust ports therein, a cup supported between the head and cylinder for rotary but non-axial movement, the inside of the cup forming a continuation ofthe bore of the cylinder and slidably receiving the head end of the piston` a spline and key connection between the piston and cup whereby rotation of the piston effects rotation of the cup, said cup having` a por-t in its end and alternately registering with the intake, and exhaust ports yin timed relation Awith the reciprocationof the piston.

the cylinder and slidably receiving the head end of the piston, means connecting th-e piston and cup so'that rotation of the piston effects rotation but non-axial movement of the cup, said cup having a port in its end and alternately registering with the intake and exhaust ports in timed relation with the reciprocati-on of the piston.

4. Apparatus of the type described including a cylinder, a piston-slidably received in the-cylinder, means for simultaneously rotating and reciprocating the piston in the cylinder, a head on the cylinder having intake and exhaust ports therein, a cup supportedbetween the head and cylinder for rotary butY non-axial movement, the inside of thecup forming a; continuationof the. bore of the cylinder and slidably receiving the head end of the piston, means connecting the piston and cup so that rotation of the pistoneffects rotation but non-axialmovement of the cup, said cup having aport `in its Vend and alternately registering With the intake and exhaust ports in timed relation with the reciprocation of the piston. Y

5. The combination defined in claim 4 wherein the cup is rotatably received in a ,counterborellin the: head end of the cylinder. l

, 5,' The combination defined in claim 4 wherein the means for effecting rotation of the piston includes a cam track extending around the' piston, and a roller cam engaging in the track and rotatably supported in a plug threadedinto the cylinder.

HOWARD S. BANCROFT.

RIJFISRENCESv CITED The following references are oi record in the le of this patent: l

i UNITED STATES' PATENTS Bancroft A- v Aug. 4, 19421. 

